This package has a dependency on gsb-desktop:
root:# slapt-get --install seamonkey
Reading Package Lists... Done
Excluding seamonkey, use --ignore-dep to override
The following packages have unmet dependencies:
seamonkey: Depends: gsb-desktop >= 2.22.1-noarch-6vl60
The following packages have been EXCLUDED:
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
Somehow I don't think Seamonkey requires GNOME.